The present invention relates to the cleaning arts. It finds particular application in conjunction with the detection of residual cleaning products remaining on pharmaceutical processing equipment after cleaning, and will be described with particular reference thereto. It should be appreciated, however, that the invention is also applicable to a variety of cleaning applications where it is desirable to ensure that the cleaning product has been thoroughly removed before reuse of the equipment.
Industries such as the pharmaceutical industry clean tanks and other processing equipment with detergent-based cleaners to remove traces of the products processed in the equipment. For pharmaceutical applications, in particular, it is important to ensure that the cleaning process has effectively removed drugs and cleaning product residues from the equipment so that there will be no cross contamination from one batch of the product to another and therefore no physiological impact. The Food and Drug Administration requires that tests be conducted to validate the cleaning process.
The level of residual cleaning product remaining on the equipment after cleaning is commonly determined by a non-specific analytical method, such as Total Organic Carbon (TOC) analysis. This approach is limited in that it only offers information about the water-soluble carbon content of all components in the residue and not about specific components in the cleaning product.
Currently, High Performance Liquid Chromatography (HPLC) is the method of choice for determining the level of residual pharmaceutical product on the equipment. The HPLC decive is calibrate using a sample of one or more of the drug additives processed in the pharmaceutical equipment. A sample of residue extracted from a wall of the processing tank, or other part of the equipment, is compared with the calibrated sample and the remaining level of pharmaceutical residue determined.
The HPCL technique is a highly sensitive method of detecting specific components in the residue. However, the detecting has not been used for detecting traces of the cleaning product on the equipment. Most components of cleaning products do not contain a detectable species, or chromophore, which can be detected by the HPLC. Moreover conventional surfactants used in the cleaning products tend to degrade over time due to the highly alkaline or acidic pH of the cleaning product and thus are not capable of acting as stable indicators for the cleaning product.
The present invention provides a new and improved cleaning composition and method for detection of residual cleaning composition after cleaning which overcomes the above-referenced problems and others.